Hello AF gurus!
I am a complete AS newb, and in my usual form I dug in deep and bought a beast in need of the Full Monty. In the interest of bragging rights as much as economy I want to do as much of the restoration as possible my self. I've been gutting and as I had suspected the subfloor wants replaced, so the body must come off.
I have a horse barn with a center isle that will easily accomodate the AS, and working in there will make the winter much more productive. I was wondering if I could take further advantage of the bulding by using the cross beams of the barn to hang the shell from (after bracing the inside of course).
Any clue how much the outer skin and windows of a 31ft 1973 Sovereign Landyacht might weigh? It'd be real handy, unless I pull down the barn on top of the trailer. Then not so much...

What has become the default standard home-made set of wooden gantry frames is usually executed with a 4x4 as cross bar located over the fore and aft roof vents. I have seen many pictures of shells your size being lifted with such a frame and have heard of no mishaps.

So judge your barn construction: Do the cross beams you intend to use equate to the strength of a pair of horizontal 4X4s? Consider current loading as well (ie., is the hay loft full of hay, or are these just rafters). Also, most people who lift their shells from above (myself included) do not use any bracing, and everything works out just fine. The shell really will hold its shape without bracing.

I have my 33' streamline in the air right now. I have it braced on the inside. I had to temporarily move a brace, and, I can attest that there's quite a bit of force on the brace. For a long trailer like mine, I think bracing is required.

.032 aluminum weighs in about .46 pounds per square foot, .040 about .57sqft. There are plenty of overlaps and there is a .040 panel above the hitch A-frame. Your wiring harnesses will probably be around 100 pounds, add in roof A/C if you have it, 5x or better sqft for the entry door. I think 4x the sheet weight for the window openings would be close enough. You'll be leaving the C and double-C channel on the floor, guesstimate the ribs and stiffeners...

My '73 27' weighed more than I thought it would, you'll appreciate having the shell safe but might be missing the best part of using portable derricks to pull shell off... using them to manipulate the frame for ease of access. Don't think twice, shimmying around on your back trying to weld and paint is such a pain and time waster you'll kick yourself for not doing it once the bruising and soreness has faded.

My 27' shell weighed a lot more when I first hoisted it because it was still somewhat attached to the frame. Oops. Those hidden rivets are tough to find.

Oh, I know that problem too well. I'm still baffled what the last thing holding mine down was. I worked for an hour to find it, and then it just popped off when I was doing something else! 81 lineal feet of trailer perimeter has a lot of rivets and surprises.

[/QUOTE] My '73 27' weighed more than I thought it would, you'll appreciate having the shell safe but might be missing the best part of using portable derricks to pull shell off... using them to manipulate the frame for ease of access. Don't think twice, shimmying around on your back trying to weld and paint is such a pain and time waster you'll kick yourself for not doing it once the bruising and soreness has faded.[/QUOTE]

I am wanting to hang the shell in the barn so I can pull the trailer out from underneath it and flip it over, weld, paint, or whatever it needs. I thought I would still build some gantries for that. I'm also looking forward to working on putting it back together INSIDE this winter.
I have considered building gantries in the barn, but didn't want to take up the whole isle way. But just using one as a central support is a great idea Al.
Now I just have to climb on top ant take off the AC without leaving a big butt shaped dent in the roof!
Thank you all for helping me hash this out.